Accident Overview
A cross-country flight ended when the airplane impacted terrain after the pilot experienced difficulty controlling the aircraft during a descent. The pilot had reported a throttle malfunction on the right engine and subsequently shut it down.
Descent and Engine Issue
While descending to the intended destination, the pilot informed air traffic control (ATC) that he could not retard power on the right engine. Later in the descent, he decided to shut down the right engine. He then communicated his desire to land at the nearest airport, and ATC provided clearance to divert.
Loss of Control
Radar data showed the airplane in a steady descent toward the airport. At about 2,500 ft mean sea level (msl), the pilot contacted ATC and stated he was trying to get the airplane under control; at that time, radar showed the airplane in a 360° right turn. The pilot then stated he was going to land on a highway. No further transmissions were received. After the right turn, the airplane continued descending through 1,300 ft msl, at which point radar contact was lost.
Witness Observation
A witness saw the airplane flying low and slow, appearing to be in stable flight with both propellers spinning. She did not observe any smoke. The airplane was flying from northeast to southwest when it suddenly descended nose first into the ground.
Impact Location
The airplane struck a gravel road adjacent to a 100-ft-tall grain silo, about 1 mile from the highway and about 3.3 miles from the airport.
Probable Cause
The pilot’s loss of airplane control during a descent to a diversion airport with only the left engine operating. A contributing factor was a malfunction of the right engine throttle, the cause of which could not be determined.